<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
			
		<style>
			#box01{
				width: 200px;
				height: 150px;
				border: 3px solid greenyellow;
				margin: 20px;
			}
			#box02{
				width: 200px;
				height: 150px;
				border: 3px solid cyan;
				margin: 50px;
			}
			
			#box03{
				width: 200px;
				height: 150px;
				border: 3px solid darkorchid;
				margin: 20px;
				float: left;
			}
			#box04{
				width: 200px;
				height: 150px;
				border: 3px solid crimson;
				margin: 50px;
				float: left;
			}
			
			#wai{
				width: 500px;
				overflow: hidden;
				border: 1px solid cadetblue;
			}
			#nei{
				width: 200px; 
				height: 100px;
				background-color: red;
				margin-top: 50px;
			}
		</style>
	</head>
	<body>
		<div>
			<div id="box01">
				
			</div>
			<div id="box02">
				
			</div>
			
			<div id="box03">
				
			</div>
			<div id="box04">
				
			</div>
			
			<div id="wai">
				<div id="nei">
					
				</div>
			</div>
		</div>
	</body>
</html>